1. Field of Invention
The present invention relates to an image compensation structure and compensation method. More particularly, the present invention relates to a method of using a reflective element to compensate for any variation in image quality on an optical sensor chip and a corresponding image compensation structure.
2. Description of Related Art
Following the rapid expansion of computer power, networking capability and multimedia development, not only can image patterns be directly captured by a digital camera, other related documents or pictures can also be captured through an optical scanner. The optical scanner converts textual or pictorial image in analogue format into digital output signals. Ultimately, a user may display, identify, edit or transfer the image file using a computer or some other electronic device.
In a scanning system, one major determinant of image quality is color temperature. The provision of an ideal color temperature enables an image sensor to operate within an optimal range so that the best pixel image quality is obtained. However, in actual manufacturing of the product, the elements may deviate from the standard design. In general, quality of the scan image may be improved and chromatic aberration of the scanned document may be reduced through adjusting the color temperature of a lamp tube. Since the response of an optical sensor chip with respect to the three primary colors (red, green and blue) are different, color temperature of the lamp tube must be adjusted to produce a balanced output. Currently, color temperature of a lamp tube is adjusted by changing the filler material inside the tube. This arrangement not only increases assembling cost, but is also demands lengthy lead time because at least two weeks are required to manufacture the lamp tube even if a suitable composition of the filler material is found.